MIVA Merchant as a storefront development and management system. It integrates catalog, product, fulfillment, maintenance, category management, shopping cart, order processing, and credit card processing in association with many of the MIVA payment providers, including Authorize.net, VeriSign.com, and several others.

Merchants use a browser-based interface and can extend or customize the system using MIVA Script (an XML-based scripting language). MIVA Merchant offers the ability to custom configure processing modules, such as payment gateways and shipping routines, which integrate with MIVA Merchant.